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Flaps or flaperons?

Old 04-08-2011, 12:18 PM
  #26  
MaxThrottle
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Default RE: Flaps or flaperons?

well ya but that seem to be his problem. So how to slow the plane down may need some explaining. He should be able to land it on a park bench but for some reason he has a little more speed than he should on a model that is fairly slow.

Thus the concern before we start changing everything on the plane.... why is it going so fast to begin with?
Old 04-08-2011, 12:38 PM
  #27  
1976kjell
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Default RE: Flaps or flaperons?

Slowing the plane down is just what Im trying to do, doing som modifications in the set up

Two reasons why its going to fast can be to high pitch on the prop and maybe a bit too much weight in the nose

Flaperons will help to reduce the speed
Old 04-08-2011, 01:39 PM
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estradajae
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Default RE: Flaps or flaperons?

I had a similar problem on my Klemm-35 from graupner...it has about 2M wingspan and even though it is a low wing plane...it has a semi-symetrical airfoil that makes it float like a sailplane...so I have hard times trying to land at the correct speed.... to fast....and it won't come down...too slow and it will likely stall and have hard time trying to recover.... The ailerons are not full span..and the plane does not include flaps (real one neither)....

Someone suggested that I should try spoilerons instead of flaperons...and it was great...I just used a small upward deflection and the plane pointed the head up a little bit...a little correction and the plane loses attitude and speed quite comfortably with no vices.

Maybe you should give it a try??
Old 04-08-2011, 01:50 PM
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Default RE: Flaps or flaperons?

Hey,

The Full Scale Cub didn't have FLAPS. Well at least not until the lastest legend cub that is........How did they slow it down when the runway was going under from a to high approach ?????

The SLIP to a landing was practiced and perfected with those airplanes and with much success after practiced !!

You too can learn to fly your model cub just as well. Practice 3 mistakes high, learn the slip technique and practice, practice, Practice...

You'll get the hang of it. I'm sure !! Best of luck with it......

PlaneD
Old 04-08-2011, 02:01 PM
  #30  
1976kjell
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Default RE: Flaps or flaperons?

Off course its possible to learn the slip, but if it can be done an easier way, thats better

Yes, my radio (as most of the todays radios) can be programmed to use the spoileron (or flaperon), so it will be easy to try up in the sky, both flaperon and spoileron.
Old 04-08-2011, 06:05 PM
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fred985
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Default RE: Flaps or flaperons?

slipping a stearman or cub was never used to slow the plane. it was used to lose altitude with out gaining speed.,,,these earlier planes didnt have flaps so the only way down when too high was the side slip.500 hours in a 450 stearman and 100 in a clip cub made me into a real expert in slips. i have a goldbergh cub that fly great with a .40. it has been modified with flaps and has no problem landing. one intersting thing is that the N number decal was the same as my stearman,,,N-4734-C,,,scale aierlons on a cub should be set up with diferentual to corect for adverse yaw.,,,also true cub aeirlons on cubs and stearmans do not work at all in a stall. not thast that matters in a model. my sig 1/4 cub flys OK with a fox .60.,,,also,,,cubs fly fine with the door and window open.
Old 04-08-2011, 06:13 PM
  #32  
delilah
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Default RE: Flaps or flaperons?


ORIGINAL: 1976kjell



30% from leading edge may include some more weight in the tail compared to the balance which the plane have now

well, there you are, your plane is nose heavy. its going to sink fast at low throttle. i bet you have up trim on the elevators? please balance your plane to achieve proper flight characteristics. thanks
Old 04-08-2011, 11:21 PM
  #33  
1976kjell
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Default RE: Flaps or flaperons?



Often a tailheavy plane is worse than a noseheavy plane, a plane which is slightly nose heavy is often more stable than a plane which has the tail down.
The old rule is that a plane should have the noseslightlydown, but for an acrobatic plane, it should be 100 % level, I guess

My cub wasslightly nose heavy, maybe its better that the cub is 100% level

Balancing the plane will be done after it has been lightly "restored"

Old 04-09-2011, 01:24 AM
  #34  
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Default RE: Flaps or flaperons?

Back when I test flew my flying buddy's CG Cub I already knew about keeping the nose up and draggy to get the glide to steepen up. The problem was that with the "usual" prop on the .60 that was on the nose even at idle when I would get the nose up the idle power in conjunction with the prop was still too much power and instead of steepening the glide it just put it into idling level flight and the model didn't want to come down. This was years ago but as I recall the typical prop for a two stroke .60 was something like a 12x6 so that's likely what it was.

That Cub was a perfect example of how it is actually possible to over power a model. When even at idle you can't get it to land a case can be made to suggest that the model is just plain overpowered.

If you insist on doing the flaperon thing despite our suggestions be sure to do the initial "practice landings" about 4 mistakes high so if/when you learn how easy it is to have it stall into a spin that you have time to pull the flaperons back up before pulling it out of the spin or spiral dive.
Old 04-09-2011, 02:12 AM
  #35  
1976kjell
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Default RE: Flaps or flaperons?

Testing the plane in high altitude when trying flaperons isobvious
Old 04-10-2011, 12:33 PM
  #36  
MaxThrottle
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Default RE: Flaps or flaperons?

As said the pitch is somewhat irrelevent to your issue since you should be able to idle down just about any prop so that it is no longer producing sufficient thrust to continue producing lift. If its nose heavy as you describe it should already be easier.

However, aircraft generally should neither be nose or tail heavy. Nose heavy is just adding extra weight load to the other end of a seesaw causing you to have to add more input force on your side, on the elevator, of the seesaw. For beginners this is sometimes used because it dampens their stick input. Expo is also use to dampen stick inputs. But you can see that it reduces the effectiveness of your elevator control; making it more mushy by making it nose heavier.

Tail heavy there is more weight on the elevator side of the seesaw making it easier to drop your end or the tail in this instance. This is considered unstable and is very sensitive to inputs; prefereable on 3D models.

There is more to it and it depends on the aircraft design but generally you want neither tail or nose heavy. Just learn to fly at the range of the model. Which is why I added the comment that many start out with these models and learn through your dilemma. So rather than masking with reconfiguring the model, see what you can do to fly the model with the techniques discussed.
One of the things that a trainer is supposed to teach you is powered throttle control, Stable approach......

Many skip this, telling by dead stick like approaches, less throttle control used, porpoising on approach, concern over tip stalls or stalls in general.

Either way you should be fine and will learn something none the less; tail heavy, nose heavy, flapperons, spoilerons, Aerodynamic center, Wings MAC, Pitch surface MAC, Neutral point, CG..... Read up on that stuff too. It may help you understand whats going on better.
Old 04-10-2011, 02:04 PM
  #37  
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Default RE: Flaps or flaperons?

With respect, I think the issue of pitch is relevant... not from the perspective of whether it is producing lift... but whether it is producing braking action.
Old 04-10-2011, 08:04 PM
  #38  
MaxThrottle
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Default RE: Flaps or flaperons?

No disagreement with what any additions can do. There are many ways to add breaking and a lower pitch prop is one of them. There are several types including a broad props in a 14". But the need to have this to handle an already slower model with any of these measures is the meaning of my comment re relevance.

I could understand if this were a jet with a low AR high wing load but it isn't. So the need for breaking...... Still if its just for fun, heck my old Kadet I had flapperons on it, it was 2 lbs over weight and I actually did land it on the top of a picknic table.
Old 04-11-2011, 07:01 PM
  #39  
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Default RE: Flaps or flaperons?

Here is an easy test to determine if it is a power system (prop, engine, RPM) issue, or control (setup or procedure) issue. Get up to altitude, ease back to idle and try to hold altitude. If the model does not descend or still can climb it is a power issue. If the model just goes into a slow descent at full up elevator it is probably not enough elevator control (could be not enough throw, nose heavy, or a combination of the two.) If the model will slow until it stalls, then you are just not slowing it down enough on approach. Now if the model goes into a stall, but at a higher airspeed then a Cub should, then it is most likely very nose heavy, overweight, or a little of both.
Old 04-17-2011, 03:03 PM
  #40  
1976kjell
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Default RE: Flaps or flaperons?

Well, it could be many reasons, but my vision is like this:

The Cub behaves as it behaves; oftenI plan to land in the start of the airstrip, but the plane almost lands on the end of the strip. The plane is landing quit fast, to be a high winged plane.I just have to accept it. I watched a youtube-video: www.youtube.com/watch?v=fV3VE-n-ky0 andthis Cub hasthe same behaviour

I had a pattern airplane (meteor) with a thicker, symmetrical wing profile, and it was much easier to land, landing slower than the cub.

But a low pitched prop and flaperons could help me get the Cub landing slower.. And of course I will test many other advices Ive got in this thread.
Old 04-17-2011, 04:17 PM
  #41  
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Default RE: Flaps or flaperons?

The guy in the vid was landing way too fast (above stall speed).  Just have to sl-o-o-o-w down earlier in the approach.
Old 04-17-2011, 07:04 PM
  #42  
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Default RE: Flaps or flaperons?

If you watch the video closely you will see he cuts the throttle on final and keeps the nose down until just above the end of the runway. In a cub this will keep quite a bit of excess airspeed and cause it to float down the runway until it can bleed off all that excess speed. Power should have been reduced on down wind, trim should be set to maintain a slow stable airspeed, and throttle used to maintain a good glide slope, and the plane should cross the end of the runway at about 5-10 feet
Old 04-17-2011, 09:16 PM
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Default RE: Flaps or flaperons?

Cfircav8r is correct!

Another thing that's fun with a Cub are slips, forward- and side-.  Another way to burn off airspeed/energy on final, and they're fun and easy.
Old 04-17-2011, 10:11 PM
  #44  
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Default RE: Flaps or flaperons?


ORIGINAL: cfircav8r

If you watch the video closely you will see he cuts the throttle on final and keeps the nose down until just above the end of the runway. In a cub this will keep quite a bit of excess airspeed and cause it to float down the runway until it can bleed off all that excess speed. Power should have been reduced on down wind, trim should be set to maintain a slow stable airspeed, and throttle used to maintain a good glide slope, and the plane should cross the end of the runway at about 5-10 feet
I fiercely agree! [8D]

And this is the field of the MFC Salzburg where the runway is quite sloping down.
Old 04-18-2011, 07:02 AM
  #45  
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Default RE: Flaps or flaperons?

There is a manuever that helps to slow the plane down and help with the increase in speed due to attitude .It's called slipping.If you have any crosswind it is very important to bank into it or it will flip the plane.But ounce you have done that you apply opposite rudder.This puts a lot of drag on the plane and keep it from gaining airspeed greatly.Although if you don' cut your throttle it won't help much.It is basicly to help if your approach is slightly high.And High wing planes land at a slower speed than Low wing planes so having any power on would only be used in high wind conditions where you may actually have to fly the plane in.I think it stabilizes alot of the airflow on the aircraft? Just know from experience No Books Hope this info was helpfull?
Old 04-18-2011, 09:12 AM
  #46  
MaxThrottle
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Default RE: Flaps or flaperons?

1976kjell; try this, slow field passes a few mistakes high as slow as you think the model can manage with a shallow decent.

You'll likely find you can get it to slow down in a pass quite a bit. Look at several of the other clipped wing cub videos doing single wheel landings and touch and goes......

Unless you're very heavy you should be able to translate a slow pass into a slow landing.
Old 04-18-2011, 04:21 PM
  #47  
1976kjell
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Default RE: Flaps or flaperons?

Yes, he keeps the nose down too long, but thats maybe typical a Goldberg Cub, it may be difficult to land it other ways. Maybe Im wrong.

I just got my cub ready to fly, after doing different things. I balanced the cub, and I experienced that it wasmuchnose heavy. I had to move a bit heavy 1700 NiCd batteripack from beneath the tank to the wall in the back of the cockpit. This measurements was done with the CG point at approximately 4 inches behind the leading edge, its equal with 36,5% behind the L.E., a bit much, but thats what stands here: http://www.carlgoldbergproducts.com/.../gpma0963.html . And its mounted 2 servos in the wing to get the flaperon-function possible. I also mounted a 14x4 APC prop on the OS 91FX.

I hope it will fly better, Im gonna try the plane in the easter, if the weather allows it
Old 04-22-2011, 10:53 PM
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1976kjell
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Default RE: Flaps or flaperons?

Yes, the cub flew better. Im quit sure that all the changes i did got an effect to the performance. I did land the cub without using the flaperons, and it landed slower anyway.

I trained with the flaperons higher in the air, and the cub really flew slow.

Its the first plane who I have flown which can fly unlimited vertically, and that was fun

Thanks for the advices
Old 04-29-2011, 05:55 PM
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Default RE: Flaps or flaperons?

OMG! Dude! Cubs aren't meant to do unlimited verticals! All I'm gonna say.
Old 05-01-2011, 07:07 AM
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Default RE: Flaps or flaperons?

ORIGINAL: 1976kjell

I have a really old goldberg cub with standard ailerons. Ive experienced that is a bit hard to land, often the plane passes the airstrip in speeds thats to fast for landing.

Im may gonna make one servo on each side of the wing, then its possible to use the flaperon function on the radio. Thats the easiest solution. Will it work, will the ailerons have enough ''power'' to steer the plane enough when I use the flaperonfunction?

Another solution is to cut aproximatly 1/3 of the ailerons and use these as flaps and have just one servo for the flaps, and one servo for the ailerons, both in the center of the wing. The reduced length of the ailerons could also reduce the ''power'' of them to steer the plane.

Any experience or opinions?
Don' know how I missed this one!
I ordered one - after seeing an example last week at the park
It is called FunCub by Multiplex and available from various sales groups - Mine is from Horizon Hobby

very scale - very light- under 10 oz ft wing loading at 590 sq inches! first pic is full scale- last pic is model
The workmanship and design on these tough foam models is exceptional -even the wheels and tires are made from the stuff. Iwill use the glider program for Radian -in my DX8 tx thisprovides adjustable flaps and or flapperons OR crow or reflex in ailerons and flaps
Sorry -no formulas today
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